Electric bikes use electric power as a primary or auxiliary power system, with manual power being an alternate system in some cases. The electric power system has at least one electric motor, a controller, storage battery, an input device and a display. In recent years, as an environment-friendly and energy-saving transportation tool, electric bikes have grown in popularity. As a key component of the electric bikes, the power system's configuration and quality often determine the overall performance of the electric bikes.
Current power systems for the electric bikes usually use a large direct current brushless motor or transverse flux motor to provide the driving force. However, the traditional drive apparatus has a large size and weight and a low efficiency, which is against the trend of electric bikes toward light weight, high power and increased efficiency to extend the range per charge.